Actuation membrane to reduce an ambient temperature of heat generating device

ABSTRACT

An apparatus including an actuation membrane unit to generate air movement in a direction of a heat generating device to reduce an ambient temperature of the device.

TECHNICAL FIELD

Embodiments described herein relate to heat management and moreparticularly to heat management using an actuation membrane.

BACKGROUND

Heat management can be critical in many applications. Excessive heat cancause damage to or degrade the performance of mechanical, chemical,electric, and other types of devices. Heat management becomes morecritical as technology advances and newer devices continue to becomesmaller and more complex, and as a result run hotter.

Modern electronic circuits, because of their high density and smallsize, often generate a substantial amount of heat. Complex integratedcircuits (ICs), especially microprocessors, generate so much heat thatthey are often unable to operate without some sort of cooling system.Further, even if an IC is able to operate, excess heat can degrade anIC's performance and can adversely affect its reliability over time.Inadequate cooling can cause problems in central processing units (CPUs)used in personal computers (PCs), which can result in system crashes,lockups, surprise reboots, and other errors. The risk of such problemscan become especially acute in the tight confines found inside laptopcomputers and other portable computing and electronic devices.

Prior methods for dealing with such cooling problems have included usingheat sinks, fans, and combinations of heat sinks and fans attached toICs and other circuitry in order to cool them. However, in manyapplications, including portable and handheld computers, computers withpowerful processors, and other devices that are small or have limitedspace, these methods may provide inadequate cooling.

In particular, cooling devices mounted on the bottom of a motherboardpresent a more acute problem. Typically, there is less room between thebottom face of the mother board and the bottom skin of a portablecomputer (i.e., notebook computer). As a result, it becomes difficult tofit a device on the underside of the motherboard to reduce thetemperature of heat generating devices mounted to the underside of themotherboard. Furthermore, mounting heat generating devices to theunderside of the motherboard also creates the undesirable effect ofsometimes generating a hot spot on the bottom skin of the notebookcomputer, further creating the need to reduce the temperature of theheat generating devices mounted on the bottom side of a motherboard. Hotspots on the bottom skin of a notebook computer are becoming even morecommonplace today as the skin of notebooks are becoming ever thinner.

One possible solution to reduce the temperature of the heat generatingdevices mounted on the bottom side of a motherboard is illustrated inFIG. 1. As illustrated in FIG. 1, a fan 102 may be placed on a side ofthe motherboard 104 to generate a flow of air across a top side andbottom side of the motherboard to cool components 106 mounted on bothsides of the motherboard. However, such a thermal solution takes awayfrom the capability to cool heat generating devices mounted on the topside which create relatively larger amounts of heat (e.g., centralprocessing units). Futhermore, the use of fans also creates undesirablenoise.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective illustration of a prior art thermal solution.

FIG. 2 is a cut-away illustration of a system incorporating an actuationmembrane unit according to one embodiment.

FIG. 3 is an illustration of an actuation membrane unit according to oneembodiment.

DETAILED DESCRIPTION

Embodiments of an actuation membrane to generate air movement in adirection of a heat generating device to reduce a temperature of thedevice and/or to reduce an ambient temperature of the heat generatingdevice, are disclosed. In the following description, numerous specificdetails are set forth. However, it is understood that embodiments may bepracticed without these specific details. In other instances, well-knowncircuits, structures and techniques have not been shown in detail inorder not to obscure the understanding of this description.

Reference throughout this specification to “one embodiment” or “anembodiment” indicate that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment. Thus, the appearances of the phrases “in oneembodiment” or “in an embodiment” in various places throughout thisspecification are not necessarily all referring to the same embodiment.Furthermore, the particular features, structures, or characteristics maybe combined in any suitable manner in one or more embodiments.

In one embodiment, as illustrated in FIG. 2, a portable computer system202 (such as a notebook computer, tablet personal computer, laptopcomputer, etc.) includes a motherboard 204, to which units are mounted.The motherboard includes a top side 204 a and a bottom side 204 a. Inone embodiment, the space between the top side 204 a of the mother boardand the inside of the computer chassis (otherwise referred to as the“skin”) is larger than the space between the bottom side 204 b of themother board and the inside of the computer chassis.

For example, as illustrated in the embodiment of FIG. 2, the spacebetween the top side 204 a of the mother board and the inside of thecomputer chassis is 8.2 mm, and the space between the bottom side 204 bof the mother board and the inside of the computer chassis is only 5.5mm. The distance between the top side 204 a and the bottom side 204 b ofthe motherboard and the computer chassis may vary in alternativeembodiments.

Electronic components may be mounted on top side 204 a and the bottomside 204 b, as illustrated. In particular, as illustrated in FIG. 1, amemory unit 206 is mounted to the bottom side 204 b of the motherboard.Alternatively, other heat generating devices may be mounted on thebottom side of the motherboard, such as a CPU, a chipset, a graphicscontroller (Grfx), or a wireless mini card.

In the embodiment illustrated in FIG. 2, an actuation membrane 208 isprovided to generate streams of air in the direction of the memory unit,or other heat generating device(s). By generating streams of air in thedirection of the heat generating device(s), the ambient temperature ofthe heat generating device, the temperature of the heat generatingdevice, and/or the temperature of the inside and outside of the localarea of the computer chassis may all be reduced. In alternativeembodiments, an actuation membrane may be mounted on the top side 204 aof the motherboard and positioned to generate a stream of air in thedirection of heat generating devices mounted on the top side 204 a ofthe motherboard.

In one embodiment illustrated in FIG. 3, the actuation membrane unit 302includes a piezoelectric or electromagnetic membrane 304 that oscillatesinward and outward, to pull air into the unit and force air out of theunit, respectively, to generate jet stream of air. More specifically, asshown in FIG. 3, when the membrane 304 oscillates outward away from theunit 302, air is pulled into the unit through the relatively smallopening 308. When the membrane oscillates inward, the air is forced outof the opening 308 of the unit 302 to produce a jet stream of air.

In one embodiment, the actuation membrane unit 302 oscillation in therange of 20-200 Hz In alternative embodiments, higher and lower rangesof oscillation are provided. Furthermore, in one embodiment, thedimensions of the actuation membrane unit include a height of 5.5 mm orless, a length of 40 mm or less, and a width of 40 mm or less. Inalternative embodiments, the dimensions of the actuation membrane unitmay vary.

In one embodiment, as further illustrated in FIG. 2, the system includesan inlet 210 to accept external air into the system, and may furtherinclude a system exit 212 to release the warmer interior air that isforced out by the jet streams generated by the actuation membrane unit

These embodiments have been described with reference to specificexemplary embodiments thereof. It will, however, be evident to personshaving the benefit of this disclosure that various modifications andchanges may be made to these embodiments without departing from thebroader spirit and scope of the embodiments described herein. Thespecification and drawings are, accordingly, to be regarded in anillustrative rather than a restrictive sense.

What is claimed is:
 1. An apparatus, comprising: an actuation membraneunit to generate air movement in a direction of a heat generating deviceto reduce an ambient temperature of the device, the heat generatingdevice is at least one of a group comprising of a memory unit, achipset, a graphics processor, and a processor, and the heat generatingdevice and the actuation membrane unit are attached to a bottom side ofa motherboard to be positioned within an interior chamber of a potablecomputer, and a space between the bottom side of the motherboard and aninner surface of a system chassis is 5.5 mm or less.
 2. The apparatus ofclaim 1, wherein the actuation membrane unit includes a piezoelectricactuation membrane.
 3. The apparatus of claim 1, wherein the actuationmembrane unit includes an electromagnetic actuation membrane.
 4. Anapparatus, comprising: a synthetic jet unit to generate air movement ina direction of a heat generating device to reduce an ambient temperatureof the device, the heat generating device is at least one of a groupcomprising of a memory unit, a chipset, a graphics processor, and aprocessor, and the heat generating device and the synthetic jet unit areattached to a bottom side of a motherboard to be positioned within aninterior chamber of a potable computer, and a space between the bottomside of the motherboard and an inner surface of a system chassis is 5.5mm or less.
 5. The apparatus of claim 4, wherein the synthetic jet unitincludes a piezoelectric actuation membrane.
 6. A system comprising: aheat generating device, the heat generating device is at least one of agroup comprising of a memory unit, a chipset, a graphics processor, anda processor; and an actuation membrane unit to generate air movement ina direction of the heat generating device to reduce a temperature ofouter surface of the system, and the heat generating device and theactuation membrane unit are attached to a bottom side of a motherboardto be positioned within an interior chamber of the system, and a spacebetween the bottom side of the motherboard and an inner surface of asystem chassis is 5.5 mm or less.
 7. The system of claim 6, wherein theactuation membrane unit includes a piezoelectric actuation membrane. 8.The system of claim 6, wherein the actuation membrane unit includes anelectromagnetic actuation membrane.
 9. A system comprising: a heatgenerating device, the heat generating device is at least one of a groupcomprising of a memory unit, a chipset, a graphics processor, and aprocessor; an actuation membrane unit to generate air movement in adirection of the heat generating device to reduce a temperature of outersurface of the system, and the heat generating device and the actuationmembrane unit are attached to a bottom side of a motherboard to bepositioned within an interior chamber of the system, and a space betweenthe bottom side of the motherboard and an inner surface of a systemchassis is 5.5 mm or less, and a graphic controller.
 10. The system ofclaim 9, wherein the actuation membrane unit includes a piezoelectricactuation membrane.
 11. The system of claim 9, wherein the actuationmembrane unit includes an electromagnetic actuation membrane.